User`s guide

Introduction

1-13

• 3T02-04, 3T05-04 and 3T01-04 - Four ring Token Ring modules

accepting data frames from and sending data frames to four

Token Ring networks. The 3T02 and 3T01 modules support UTP

and STP cable types respectively, while the 3T05 supports either

UTP or STP.

• 3F00-01 and 3F55-01 - DAS (dual-attached station) FDDI

modules. These modules transfer packets from and to a FDDI

network. The front panel accepts media interface connectors

(MICs) for multi-mode ﬁber (MMF) such as the 3F00-01, or

single mode ﬁber (SMF) such as the 3F55-01. Both modules

support an external optical bypass switch (OBS). Each has a

built-in DMA controller, but not a general purpose processor, so

the station management functions are performed by the PPE.

• 3H02-04 and 3H08-04 - Four port 100 Mbps Fast Ethernet Switch

modules. These modules support UTP via RJ71 connectors and

ﬁberoptic via ST connectors respectively.

Modules are described in greater detail in the documentation that

accompanies each module.

1.6.8 Power Supply

The ATX comes with one self-ranging power supply. An optional

redundant power supply is also available that automatically takes

over when the primary power supply fails. Each power supply has

its own power entry module and fuse assembly to allow the use of

separate power sources. When both supplies are used the load is

balanced between the power supplies.

1.7 BRIDGING FUNCTIONS

The basic bridging function of an ATX is to transparently forward

data packets to the network segments (LANs) it interconnects.

Incoming packets are stored momentarily while the ATX checks

their destination addresses against the ATX's address table. If a

packet's destination address is not on the same network segment